Question

使用单链表，我将返回一个Set c，其中包含仅在集合A中找到但不在集合B中找到的元素。

Set A包含：30,20，item2，item1,10,26

Set B包含：88，item3,30，item4,26,100

A.complement（B）;应该输出{20 item2 item1 10}，

但是我得到{20 item2 item1 10 26}并且'26'不应该在集合中。即使在列出清单图表之后，我也无法弄清楚出了什么问题。

public boolean otherContain(Object obj) { // returns true if object is
                                            // inside singly linked list
    Node cur = head.next;

    while (cur != null) {
        if (cur.object.equals(obj))
            return true;
        else
            cur = cur.next;
    }

    return false;
}


public Set complement(Set a) {// return set containing elements only in A
                                // not shared with B
    Set c = new Set();
    Node curC = c.head;
    Node cur = head.next;

    while (cur != null) {

        if (a.otherContain(cur.object)) {
            cur = cur.next;
        } else if (!a.otherContain(cur.object)) {
            curC.next = cur;
            curC = curC.next;
            cur = cur.next;
        }
    }
    return c;
}

*************更新的工作方法************************

    public Set complement(Set a) {// return set containing elements only in A
                                // not shared with B
    Set c = new Set();
    Node newNode = c.head;
    Node cur = head.next;

    while (cur != null) {

        if (a.otherContain(cur.object)) {
            cur = cur.next;
        } else if (!a.otherContain(cur.object)) {
            newNode.next = new Node(cur.object, newNode.next);
            cur = cur.next;
        }
    }
    return c;
}

Answer 1

您的问题是您正在重复使用输出Set中输入Set的节点，因此您添加到输出Set 10的最终节点仍然是指输入Set的最后一个节点 - 26.您应该创建输出集的新节点。

public Set complement(Set a) {
    Set c = new Set();
    Node curC = c.head;
    Node cur = head.next;

    while (cur != null) {  
        if (!a.otherContain(cur.object)) {
            Node newNode = new Node();
            newNode.object = cur.object;
            newNode.next = null;
            curC.next = newNode;
            curC = curC.next;
        }
        cur = cur.next;
    }
    return c;
}

为什么我的方法在不应该打印出列表的最后一个元素时？

1 个答案: